[yocto] bblayer priorities ignored for bbappends?

[Nikolay Dimitrov]

Hi Paul, Tobias,

On 04/08/2015 11:55 AM, Paul Eggleton wrote:
> Hi Tobias,
>
> On Wednesday 08 April 2015 08:54:20 Tobias Olausson wrote:
>> I just had a weird experience with yocto and I wanted to know if the
>> described behaviour is intentional.
>>
>> I have a layer with priority 7 containing a recipe, foo.bb. In another
>> layer, with priority 8, there is a foo.bbappend. Finally, I just added
>> another layer, with priority 9, where foo.bb is redefined as a binary
>> recipe.
>>
>> When I added the last layer, I expected that to take precedence over the
>> other two. However, the bbappend for foo is still applied (which in this
>> case changed the SRC_URI, making the whole binary recipe moot). Is this
>> really the way it's supposed to be? I would expect that lower layers cannot
>> influence layers with higher priority at all, but that does not seem to be
>> the case.
>
> That is the case, yes - bbappends are always applied. As far as I am aware
> this is the first time this kind of situation has been asked about though so
> it's probably just that we didn't consider it before.
>
> Presumably you could use a bbappend rather than a recipe in the last layer?
> You might need to stub out some of the functions of course, but it should be
> possible.

Thanks for touching the important subject. Indeed, this is an issue as
sometimes the bbappend change is generic and can be reused by the
customer layer(s), and sometimes the change is not appropriate and
needs to be undone.

I would agree that both cases are legitimate and would look for ideas
how it can be resolved in a logical way.

Regards,
Nikolay

PS: I can give examples, but don't want to drift the discussion towards
my topics.